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101.
We studied the validity of the Finnish hospital discharge register data on coronary heart disease (CHD) for the purposes of epidemiologic studies and health services research. The Finnish nationwide hospital discharge register (HDR) was linked with the FINMONICA acute myocardial infarction (AMI) register for the years 1983–1990. The frequency of errors in the HDR was assessed separately. Between 8% and 13% of hospitalized AMI events registered in the AMI Register were not found in the HDR with an ICD code for CHD. Problems with the register linkage and the use of some ICD code other than one of the codes for CHD explained these missing events. The frequency of errors in the personal identification number was about 5% in the early 1980s. After 1986 errors were found only occasionally. The diagnosis recorded in the HDR was the same as that in the discharge sheet in about 95% of hospitalizations. The positive predictive value of the ICD code 410 (AMI), compared with the FINMONICA definite+possible AMI category, was very high and stable, about 90% in all areas and all hospitals, but it sensitivity varied from 50% at local hospitals to 80% at central hospitals. In summary, data on CHD obtained from the Finnish hospital discharge register give, on average, a correct picture on changes in the occurrence of AMI in Finland and can, with necessary caution, be used in epidemiological studies and health services research. However, the classification of individual cases is not standardized in the HDR, but varies over time, between geographical areas and the levels of care. Therefore, these data should not be used without confirmation in studies where correct classification of individual outcomes is of crucial importance, such as follow-up studies and case-control studies.  相似文献   
102.
The use-effectiveness of an intrauterine contraceptive device releasing 20 mcg of levonorgestrel daily (Lng-IUD), and of a Nova T copper-releasing IUD, were studied in a randomized, comparative multicenter trial. The Lng-IUD was inserted in 1821, and the Nova T in 937 women. The 12-month net pregnancy rate with the Lng-IUD (0.1 per hundred women) was significantly lower than that with the Nova T (0.9 per hundred). Removal rates for menstrual problems and/or pain were similar for the two methods (net rates 7.5 and 8.7, respectively). The 12-month continuation rates were 82.2 for the Nova T and 79.7 for the Lng-IUD. The reduction of the bleeding led to oligomenorrhea and amenorrhea in users of the Lng-IUD; the removal rate for these reasons was 1.4. The removal rate for hormonal side effects with the Lng-IUD was 2.4. Blood hemoglobin concentrations increased among users of the Lng-IUD and decreased among users of the Nova T. The results show that the Lng-IUD was a highly effective contraceptive method which reduced menstrual bleeding. It is a promising alternative for women desiring a highly effective method for long-term use.  相似文献   
103.
Clinically diagnosed trigonocephaly have been treated by a standard surgical technique developed at Göteborg University Craniofacial Unit. To evaluate the technique we designed a study to include both subjective and objective assessments. Of 30 patients operated on between 1988-1997, 15 patients with at least three years postoperative follow-up have been included. An evaluation of the surgical outcome of the bitemporal width, the forehead contour, and the intercanthal distance was made both subjectively using a visual analogue scale (VAS) and objectively with analyses of cephalograms taken preoperatively and postoperatively at 3 and 5 years of age. For the subjective evaluation a control group of 10 randomly selected children from a Child Welfare Centre were selected. For the objective evaluation the control group consisted of cephalograms from children born with cleft lip and palate who were matched regarding sex and age. Both cephalometric analysis and subjective studies of the outcome indicated improvement. When the forehead contour was investigated the number of patients who had been improved or corrected completely was higher when evaluated subjectively. When interorbital distance on cephalograms and intercanthal distance scores on VAS were evaluated, again the subjective study indicated improvement in more subjects.  相似文献   
104.
Summary We measured serum lipids, lipoproteins and postheparin plasma lipases, lipoprotein lipase and hepatic lipase, in 12 female patients with Type 1 (insulin-dependent) diabetes (postglucagon C-peptide undetectable), in 11 female insulin-treated patients with Type 2 (non-insulin-dependent) diabetes (postglucagon C-peptide >0.60 nmol/l) and in 16 non-diabetic female control subjects. These three groups of subjects were similar with respect to age and obesity. Insulin dose was similar in patients with Type 1 and with Type 2 diabetes. HDL and HDL2 cholesterol were lower in patients with Type 2 diabetes than in non-diabetic control subjects (p<0.05) but did not differ between patients with Type 1 diabetes and non-diabetic control subjects. No difference in lipoprotein lipase activity was seen between the groups. The highest levels of lipoprotein lipase and hepatic lipase activities were observed in patients with Type 2 diabetes. Lipoprotein lipase activity correlated significantly with HDL cholesterol in patients with Type 1 diabetes (p<0.01) and in patients with Type 2 diabetes (p<0.001) but not in control subjects. Hepatic lipase activity did not correlate significantly with HDL cholesterol in any of the groups. In conclusion, postheparin plasma lipoprotein lipase and hepatic lipase activities do not seem to explain the difference in HDL cholesterol concentration between patients with Type 1 and Type 2 diabetes.  相似文献   
105.
Diabetes and atherosclerosis: an epidemiologic view   总被引:17,自引:0,他引:17  
Diabetes is associated with changes in plasma lipids and lipoproteins into atherogenic direction. In IDDM these changes are small or absent if good metabolic control can be maintained. Diabetic nephropathy is, however, associated with the appearance of dyslipoproteinemia. In NIDDM plasma total and VLDL triglyceride levels are elevated, and HDL-cholesterol level is decreased, and this pattern of dyslipoproteinemia does not always respond to improved control of hyperglycemia. Abnormalities of lipoprotein metabolism, not reflected in conventional plasma lipid and lipoprotein level measurements, and glucosylation of lipoproteins and resulting alterations in lipoprotein catabolism may be of importance in the enhanced atherogenesis in diabetes. Both IDDM and NIDDM are associated with an increased frequency of hypertension, but the underlying mechanisms appear to be different. In IDDM hypertension is usually associated with the development of diabetic nephropathy and thus with a long duration of the disease. In NIDDM hypertension is often present already at the time of diagnosis, and also in IGT, the precursor stage of NIDDM, the prevalence of hypertension is already increased. Obesity explains only in part the high prevalence of hypertension in patients with NIDDM. Diabetes is known to be associated with multiple abnormalities in hemostatic factors and, although these abnormalities may contribute importantly to the increased risk of ASVD in diabetic patients, information about their real role is scanty and conflicting. The impact of general major risk factors for ASVD, elevated plasma cholesterol, elevated blood pressure, and smoking, on the risk of ASVD appears to be similar in diabetics and nondiabetics. Only a relatively small proportion of the excessive occurrence of ASVD in diabetics can, however, be explained by the effects of diabetes on the levels of general risk factors for ASVD. This proportion mediated through the effects of diabetes on risk factors is larger in female diabetics than in male diabetics. The major proportion of the excess of ASVD in diabetics remains, however, unexplained and must be due to effects of diabetes itself through mechanisms that are incompletely understood.  相似文献   
106.
New pasture plants intensify invasive species risk   总被引:1,自引:0,他引:1  
Agricultural intensification is critical to meet global food demand, but intensification threatens native species and degrades ecosystems. Sustainable intensification (SI) is heralded as a new approach for enabling growth in agriculture while minimizing environmental impacts. However, the SI literature has overlooked a major environmental risk. Using data from eight countries on six continents, we show that few governments regulate conventionally bred pasture taxa to limit threats to natural areas, even though most agribusinesses promote taxa with substantial weed risk. New pasture taxa (including species, subspecies, varieties, cultivars, and plant-endophyte combinations) are bred with characteristics typical of invasive species and environmental weeds. By introducing novel genetic and endophyte variation, pasture taxa are imbued with additional capacity for invasion and environmental impact. New strategies to prevent future problems are urgently needed. We highlight opportunities for researchers, agribusiness, and consumers to reduce environmental risks associated with new pasture taxa. We also emphasize four main approaches that governments could consider as they build new policies to limit weed risks, including (i) national lists of taxa that are prohibited based on environmental risk; (ii) a weed risk assessment for all new taxa; (iii) a program to rapidly detect and control new taxa that invade natural areas; and (iv) the polluter-pays principle, so that if a taxon becomes an environmental weed, industry pays for its management. There is mounting pressure to increase livestock production. With foresight and planning, growth in agriculture can be achieved sustainably provided that the scope of SI expands to encompass environmental weed risks.Livestock production is already the largest land use on earth, accounting for 30% of global land area (1). Nevertheless, growing demand means that production must rise more than 50% by 2050 (2) as global population size and per capita consumption increase (25). Responding to this demand, agribusiness* is developing and marketing new taxa of forage plants designed to increase pasture productivity. Through artificial selection and hybridization, public and private organizations are developing plant taxa that are more productive and more tolerant of disease and environmental extremes. At the same time, there is a strong campaign for sustainable intensification (SI) of agriculture. One approach to SI is to increase production on some lands while sparing others for conservation (5, 6). Agricultural intensification using new pasture taxa may thus be an efficient way to help meet rising demand and reduce some of the social and environmental costs of traditional agriculture (5). However, perversely, it may drive another environmental problem because pasture plants can invade the native ecosystems that “land sparing” is designed to protect (7).Environmental weeds are invasive alien plants that establish in natural areas (e.g., remnant native vegetation and conservation reserves), usually to the detriment of native species (8). Environmental weeds threaten biodiversity, compromise ecosystem function, and cost billions of dollars to manage each year (915). Many have been introduced as pasture forages (7). For example, in Australia, the introduced pasture species Andropogon gayanus (gamba grass) increases wildfire intensity fivefold, reducing carbon stores and transforming species-rich native savannah to exotic-dominated grassland. Predicted to invade up to 380,000 km2 of northern Australia (16), gamba grass invasion has increased the cost of fire management by an order of magnitude, from less than AUD$2000 for each fire to as much as AUD$43,000 per fire (16). The possibility that SI may worsen problems like these warrants serious consideration, yet the topic remains controversial and the risks are not fully acknowledged (Fig. 1) (5, 17).Open in a separate windowFig. 1.The Undoolya Wattle Acacia undoolyana, nationally listed as vulnerable, standing dead in a sea of invasive pasture grasses (largely buffelgrass Pennisetum ciliare). This species occurs in several small populations in a 165-km2 area of the East McDonnell Ranges in central Australia. Fires in 2013 killed many of the trees in the N''Dahla Gorge population (pictured). Although the wattle is threatened by hot fires, the dominant role that buffelgrass plays in altering the fire regime is not mentioned on the information board. Introduced pasture grasses are contentious in the Australian rangelands because they are used by the cattle industry, but also are highly invasive, fueling intense fires that kill woody plants and transform ecosystems. Photograph by D.A.D.Here, we take a global perspective to consider whether new pasture taxa are likely to become environmental weeds (hereafter “environmental weed risk”) and whether there are mechanisms in place to limit potential risks. Although we focus specifically on the risk of new pasture taxa becoming environmental weeds, we acknowledge that very similar risks, and likely solutions, apply to other systems of production including bioenergy (18, 19), carbon sequestration (20), forestry (21), and horticulture (21, 22). We find that increased environmental weed risk from new pasture taxa presents a major challenge to increasing livestock production in a way that is consistent with SI (5). Nevertheless, there are practical solutions to reduce these risks that can be informed by new research and extend from government regulation to responsible product development and consumer choice (Fig. 2).Open in a separate windowFig. 2.Pathways influencing the risk that pasture taxa will invade natural areas and become environmental weeds. Currently, (A) economic models inadequately accommodate long-term social and environmental costs. Governments impose few or no regulations on new pasture taxa despite having to provide public funds to manage environmental weeds that were initially introduced as pasture. Most research into new taxa does not consider environmental weed risk. With little self-regulation, agribusiness may therefore inadvertently increase the environmental weed risk. Solutions to these problems (B) include closer interaction and feedback among researchers, government, and industry, government initiatives to promote low-risk pasture development, and industry-led certification enabling consumers to reward environmentally responsible pasture development. *See Fig. 3 regarding protocols for weed risk assessment.  相似文献   
107.
Summary Finland has marked regional differences in the occurrence of coronary heart disease (CHD). Although the causes for these differences in CHD mortality and morbidity in the Finnish population are unknown, it offers an excellent opportunity to investigate the effects of non-insulin-dependent diabetes mellitus (NIDDM) on CHD risk in two populations differing significantly with respect to the occurrence of CHD. Therefore, we carried out a 7-year prospective population-based study including a large number of patients with NIDDM (East Finland: 253 men and 257 women; West Finland: 328 men, 221 women) and corresponding non-diabetic subjects (East Finland: 313 men, 336 women; West Finland: 325 men, 399 women). In both study populations the presence of NIDDM increased significantly the risk for CHD events (CHD mortality or all CHD events including CHD mortality or non-fatal myocardial infarction). Diabetic men had 3–4 fold higher and diabetic women 8–11-fold higher risk for CHD than corresponding non-diabetic subjects. Both non-diabetic and diabetic subjects had odds ratios (East vs West) for CHD events of about 2 indicating a similar East-West difference in the CHD risk. Regional difference was quite similar in men and women. These results imply that factors related to NIDDM, independently of conventional risk factors and the occurrence of atherothrombosis in the background population, must play a major role in the pathogenesis of atherosclerotic vascular disease in NIDDM diabetes.Abbreviations CHD Coronary heart disease - NIDDM non-insulin dependent diabetes mellitus - MI myocardial infarction  相似文献   
108.
A cross-sectional study on the prevalence of atherosclerotic vascular disease (ASVD) and its risk factors in non-insulin-dependent diabetic and nondiabetic subjects was carried out from 1982 to 1984 in East Finland (Kuopio) and West Finland (Turku), two areas known to differ markedly in prevalence of ASVD in the nondiabetic population. A total of 510 diabetic and 649 nondiabetic subjects aged 45-64 yr were examined in East Finland and 549 diabetic and 724 nondiabetic subjects of the same age in West Finland. In both areas and in both sexes the prevalence of coronary heart disease (CHD), stroke, and intermittent claudication was higher in diabetic than in nondiabetic subjects. Both in diabetic and nondiabetic subjects the prevalence of ASVD was higher in East Finland than in West Finland. In men, the East-West difference in the prevalence of symptomatic CHD and claudication was greater in diabetic than in nondiabetic subjects. In both areas and in both sexes the serum lipid pattern was more atherogenic and hypertension was more frequent in diabetic than in nondiabetic subjects. In both diabetic and nondiabetic subjects, serum total-cholesterol level was somewhat higher and hypertension was more frequent in East Finland than in West Finland. The East-West difference in serum total-cholesterol was greater in diabetic than in nondiabetic subjects. In multiple logistic analyses including cardiovascular risk factors, diabetes status, and area of residence, residence in East Finland was found to be, in addition to diabetes, a strong independent factor associated with CHD, particularly in men.  相似文献   
109.
The effect of metoprolol on indices of infarct size and left ventricular function was compared with that of placebo in a double-blind randomized trial in patients with definite or suspected acute myocardial infarction. Intravenous metoprolol (15 mg) or placebo was given within 24 h of the onset of symptoms, and oral treatment (200 mg daily) was continued for 15 days. Thirty-five patients received metoprolol and 34 patients placebo. The mean (+/- SD) of maximal creatinine phosphokinase (CK)-MB activities was 142 +/- 110 IU/l in the placebo group and 74 +/- 72 IU/l in the metoprolol group (p less than 0.001). The ECG QRS score at discharge from hospital was 5.22 +/- 4.47 and 4.61 +/- 3.06 (NS), respectively. Global left ventricular ejection fraction at rest was 44 +/- 14 and 51 +/- 15% (p = 0.054), respectively, and no change occurred in either group from rest to peak exercise. Ventricular fibrillation occurred in 1 placebo patient during the first day in hospital and in 1 metoprolol patient on the 14th day. Holter monitoring revealed no significant difference in the occurrence of ventricular arrhythmias during the first 24 h. Smaller enzyme release and higher ejection fraction suggest myocardial protection by early metoprolol treatment in acute myocardial infarction.  相似文献   
110.
Coronary heart disease in insulin-dependent (IDDM) and in non-insulin-dependent diabetes (NIDDM) is associated with lipid and lipoprotein changes favouring atherosclerosis. Whether lipid and lipoprotein abnormalities are associated also with peripheral vascular disease in both types of diabetes is largely unknown. Therefore, we studied lipid and lipoprotein levels and their association with claudication in a representative sample of diabetic and non-diabetic subjects in East Finland. Altogether 87 subjects had IDDM (43 men, 44 women), 264 subjects NIDDM (126 men, 138 women) and 120 subjects were non-diabetic controls (63 men, 57 women). Patients with IDDM had an increased level of HDL and HDL2-cholesterol and patients with NIDDM a decreased level of HDL and HDL2-cholesterol and an increased level of total, LDL and VLDL triglycerides than did non-diabetic subjects. Analyses in both types of diabetes by claudication status revealed that total and LDL-cholesterol and total and VLDL triglycerides tended to be higher and HDL and HDL2-cholesterol lower in those having claudication as compared to those without a claudication symptom. Similarly, total cholesterol/HDL-cholesterol ratio and LDL-cholesterol/HDL-cholesterol ratio were also more atherogenic in patients with claudication than in those without claudication. In conclusion, our results indicate that in both types of diabetes peripheral vascular disease is associated with lipid and lipoprotein abnormalities favouring atherosclerosis.  相似文献   
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